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Triphasic QRS morphology: What is the mechanism?
Hans C Helseth1, William H Frick2
1Medical College of Wisconsin, 8701 W Watertown Plank Rd, Milwaukee, WI, USA.
Journal of Electrocardiology
|September 18, 2025
Summary
This study details an electrocardiogram (ECG) showing a unique triphasic QRS morphology variation. We explore the underlying mechanisms and discuss the significant clinical implications of this ECG finding.
Area of Science:
- Cardiology
- Medical Diagnostics
Background:
- Electrocardiograms (ECGs) are fundamental tools for assessing cardiac electrical activity.
- Variations in QRS morphology can indicate underlying cardiac conditions.
Purpose of the Study:
- To present a novel electrocardiogram finding: triphasic QRS morphology variation.
- To elucidate the potential mechanisms driving this specific ECG pattern.
- To discuss the clinical relevance and implications of observing this variation.
Main Methods:
- Analysis of electrocardiogram (ECG) tracings exhibiting unusual QRS complex shapes.
- Review of relevant physiological and pathological processes that could lead to altered ventricular depolarization.
- Correlation of the ECG findings with potential clinical scenarios.
Main Results:
- Identification and detailed description of an electrocardiogram with a distinct triphasic QRS morphology.
- Postulation of electrophysiological mechanisms responsible for the observed QRS variation.
- Discussion of potential associations with specific cardiac conditions or physiological states.
Conclusions:
- Triphasic QRS morphology variation on an ECG is a notable finding.
- Understanding the mechanism is key to interpreting its clinical significance.
- Further investigation may refine diagnostic and prognostic value.
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